"Why we are here ?" vs "Why are we here ?"

Question

I would like to ask this question to an audience during a presentation and follow with an explanation. I wonder which form is correct—Why we are here? or Why are we here?

I understand that the correct form should be Why are we here?, but the form Why we are here in the context of religion, for example, is quite popular.

Is Why we are here? a grammatical mistake? If so, then what is the correct context in which to use Why we are here?

I tried to search Google, but the sentence is too general and it is hard to find anything.

Answer 1

A rhetorical question is not meant to be answered and thus becomes a leading question, and therefore the declarative why we are here is rather suitable than the imperative why are we here having people construe to immediately vacate the premises not to mention during your presentation for the more significant things to do.

Answer 2

Why we are here? in common American English, would be a preface to an answer to a question regarding a specific situation, quandary, or problem.

Example:

Why we are here is easy to explain. We offered an inferior product at too high a price. And so, accordingly, we went out of business because the darned thing wouldn't sell.

Why are we here? is generally a philosophical question, followed by more specific queries.

Example:

Why are we here? I mean, what is our purpose on this planet, and in this existence? Is there a grand design, or is it all random happenstance?